电动汽车线控转向系统性能分析与参数优化

Performance Analysis and Parameters Optimization of Steerby Wire System in Electric Vehicle

研究电动汽车操纵稳定性优化问题,电动汽车采用线控转向系统,可靠性差,成本高。为提高操纵稳定性和主动安全性,提出对设计的线控转向系统的实体结构进行适当简化,建立了电动汽车线控转向系统的动力学模型。然后,研究了电机及减速器等的结构参数对系统频率响应特性和时域响应特性的影响,进行了电动汽车线控转向系统性能分析。最后,对系统的稳定性条件,采用非线性带约束优化算法进行了电动汽车线控转向系统的参数优化仿真。结果表明,经过参数优化后,电动汽车的操纵稳定性大大提高,可用于指导转向系统的参数设计与匹配。

More and more popular electric vehicles are excellent application platforms for steer by wire system. Handling stabilities and active safety are greatly improved when steer by wire system is adopted in electric vehicle. Firstly, dynamics models of steer by wire system were built after simplifying the solid structures. Then, the influences of the parameters of motor and speed reducer on the characteristcs of system frequency response and time domain re- sponse were analyzed. The performance analysis of steer by wire system was done. Finally, stability condition of steer by wire system was researched, and nonlinear optimization algorithm with constraints was adopted for the parameters optimization of steer by wire system. The results show that handling stabilities of electric vehicle is greatly improved so as to be used for parameters design and match for electric vehicle.